This disclosure relates to the prior art fields of registration of 2D and 3D images; CPR visualization of vessels; and localizing catheters and guide wires (or other instruments) in 2D images.
More particularly this disclosure relates to the prior art field of fluoroscopy controlled, interventional repair of Abdominal Aortic Aneurysms (AAA), which is a disease of the abdominal aorta. See prior art FIGS. 1A,B,C. This disease is usually treated by inserting stent grafts 10 into the aorta 11 to remodel the organ. Through the groin arteries 13, guide wires 12 and catheters are inserted through which one or more stent grafts 10 are placed (FIGS. 1A,B,C).
Important for the delivery of these grafts is to stay in a determined “landing zone”. The object is to place the stent in a healthy area without occluding any important vessel branches, like e.g. the renal arteries. A sensitive point during the intervention is the release of the main stent in the aorta (FIG. 1C). Sometimes the finite stent must be mounted from different stent parts, e.g. from stents covering the leg arteries, the aorta etc.
To not have to inject contrast medium permanently to control this complex stent positioning, as shown in FIG. 2A,B,C it is possible in a known method to overlay a registered 3D volume 15 showing the (segmented) relevant part 14 (aneurysm) of the aorta 11 (FIG. 1A,B,C) to guide the positioning of the stent 10 (FIG. 1). Knowing the registration of the volume 15 to the C-arm of an angiography system and the projection geometry, the volume 15 can be projected anatomically correct to the 2D fluoro (fluoroscopy) image 16 of the angiography system. See prior art FIGS. 2A,B.
Thus prior art FIGS. 2A,B show a 2D3D overlay. If the 3D volume 15 is registered to the C-Arm and the projection geometry of the C-Arm is known (FIG. 2A), the 3D volume 15 can be overlaid anatomically correct to the 2D fluoroscopic image 16 (FIG. 2B). The visualization can also follow each angle change etc. of the C-Arm.
A visualization problem can be that during this overlay the aorta may look different than in the diagnostic images the physician usually uses for planning the intervention. For planning purposes, the 3D image information gets displayed as so called “Curved MPRs (Multi-Planar Reconstruction) (CPRS (Curved Planar Reconstruction))” (see Armin Kanitsar, Dominik Fleischmann, Rainer Wegenkittl, Meister Eduard Gröller, “Diagnostic Relevant Visualization of Vascular Structures”, Technical Report TR-186-2-04-02, Jan. 20, 2004, TU Vienna). Prior art FIGS. 3A,B,C basically provide a standardized view on the organ by straightening the aorta 17. See prior art FIG. 3C.
Prior art FIGS. 3A,B,C thus show possibilities to visualize the aorta. FIGS. 3A, B show the “usual” way to visualize aortic angiographies, the MPR (Multi-Planar Reformation) mode—respectively a volume rendering VRT shown in FIG. 3B. Another way, especially for segmented vessels, is the display as a so called CPR (Curved Planar Reformation) which offers a rotation around the center line 18A (FIG. 3C). Sometimes the aorta 17 is stretched, so that the center line 18A becomes a straight line 18B, which provides a standardized view onto the organ (see Kanissar et al., supra).